Is it possible to create an outline border with radius?

Question

I known you can add an outline border with CSS3.

outline: 10px solid red;

Now I was wondering how I can add also a radius to that outline border.

I have tried this one, but doesn't work:

.radius {
    padding: 20px 60px;
    text-transform: capitalize;

    -moz-outline: 10;
    outline: 10px solid red;

    -webkit-border-radius: 40px;
    -moz-border-radius: 40px;
    border-radius: 40px;    
}

Answer 1

Try using CSS-Tricks' Infinite Borders technique and applying border-radius.

This method will require borders and box-shadow and not outline.

img {
    border-radius: 4px;
    /* #1 */
    border: 5px solid hsl(0, 0%, 40%);
    
    /* #2 */
    padding: 5px;
    background: hsl(0, 0%, 20%);
    
    /* #3 
    outline: 5px solid hsl(0, 0%, 60%); */
    
    /* #4 AND INFINITY!!! (CSS3 only) */
    box-shadow:
        0 0 0 10px red,
        0 0 0 15px orange,
        0 0 0 20px yellow,
        0 0 0 25px green,
        0 0 0 30px blue;
    
        
    /* If you could do pseudo elements 
       you could get a few more... */
    
    /* Also, HSL is awesome but don't use it if
       you need super old browser support */
}

body { padding: 50px; text-align: center; }

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